Merge pull request #5175 from roopekv/stdcall-placement-when-trailing-return-type

Update stdcall.md

Author: Court72

docs/cpp/stdcall.md

@@ -13,6 +13,8 @@ The **`__stdcall`** calling convention is used to call Win32 API functions. The
 ## Syntax
 
 > *return-type* **`__stdcall`** *function-name*[**`(`** *argument-list* **`)`**]
+>
+> **`auto`** **`__stdcall`** *function-name*[**`(`** *argument-list* **`)`**] [ **`->`** *return-type* ]
 
 ## Remarks